Stripped crankcase on my Honda 300trx

This time when I went to change my oil and pulled the plug I noticed that it came out with more force than it should. If I remember right the last time I put it in it felt strange. Anyway drained it and put it back it. Was taking more force and I was like that's not right but it took more to get it out.... anyway it would not snug up. I pulled it out and then saw aluminum in its threads and the hole was mostly smooth.

Read a blog post somewhere about drilling out with 29/64 bit and aN then tap it out to 1/2x20 more common automotive plug. This is Th E route I'm 99% leaning too. It also said don't use the self tapping ones as some have had I wedge their crankcaservices apart.

Any thoughts? Should I just tap it and use a plug or should I put one of those piggyback plugs unit so I don't mess with the big plug as much or just make sure not to he man tighten it like the previous owners must have done in this machines previous life?

 

Re-tap and be careful with it in the future. Someone probably stuck the plug in a socket on a cordless impact and jammed it home at some point.

 

I'm thinking reap aswell. Just gun shy now.

But the crush washer on the plug I noticed was bent into a concave shape someone out it in there so tight!! It was so pressed to the plug I thought it was a shoulder till I just recently looked at it!! Never noticed The washer distortion either!

 

I'd say retap as well. Take care and do it right and you should be all set for years to come. Good luck and watch the metal shavings in the crank case.

 

Said coat the tap with grease and clean it...that's a good idea. As well as saving old oil and pour it through a few times. Too bad I drained it into a dirty drain pan prior to this!!. I will use diesel or get some old oil or something I have here. Maybe some out of my used oil paIL and dip it out...or just some of this cheap old oil I have sitting around in qt bottles.

 

You can dip the drill bit in grease too. Won't hurt it. I'm real ocd about stuff like this I'd probably use diesel. Just for my piece of mind. Sounds like you got it covered though.

 

buy the plug first, find one with the molded in o ring seal, you wont have to crank on it that way. a standard twist drill, opening up a hole like that will not make a true hole. be careful.

 

I will drill then use a tap to cut new 1/2 threads

 

Said to only drill part way through the hole as well??? Don't know really.

 

I would try to drill it out with a T-handle and a sharp bit. You could very easily make a mess with a power drill in that relatively thin aluminum. Even if it takes 2 or 3 sizes to get to the final size.

 

Good sugestion. I had the T handle for the tap. Didn't think about hand drilling. I was just going to go real slow but will try this first

 

Doesn't need to be super round...just not fubar'd with a power drill....if the bolt cap is making the seal against the case.

 

When orange county choppers use to be on and I watched that I always was amazed to see them tapping holes with a power drill. They did it all the time!!! I mean even if they were cleaning paint out of holes I don't think I'd use a drill!!

I guess when your good though????

 

Hand tap only, unless you like fixing problems that could be prevented.

 

Ahhh.....the magic of television.

 

I don't know if it was majic. They were working on a bike and talking about something and he was taping something. And they showed it. The taping was not the focus of the shot it was whatever they were talking about.

 

How many times did they f it up and not show it on TV? One will never know.

 

Not sure. But the amount of times I saw it over many years of The show being on leads me to believe that the did it all the time. And it wasent just one guy it was many.

And like I said many times the tapping was not even the focus of the shot but just them talking and working. Sometimes it was a closeup of what they were doing but usually not really.

That said I am not tapping with my drill...never thought about it!

 

In aluminum? That's a horse of a different color.